JP2018128117A - Actuator - Google Patents

Abstract

[PROBLEMS] To provide an actuator capable of simplifying the configuration for connecting a ball screw nut and a rod and thus facilitating manufacturing. SOLUTION: A housing, a ball screw shaft that is housed in the housing and is rotated and driven, a ball screw nut that is screwed onto the ball screw shaft, and a rod that is crowned on the outer peripheral side of the ball screw nut. and a clamp mechanism for fixing the rod to the ball screw nut by tightening the rod from the outside. [Selection drawing] Fig. 7

Description

  The present invention relates to a rod-type actuator, and more particularly to a device devised so as to simplify the configuration for connecting a ball screw nut and a rod and to facilitate manufacturing.

For example, Patent Literatures 1 to 3 disclose the conventional actuators.
First, the electric linear actuator described in Patent Document 1 includes a rotating shaft that is rotated by an electric motor in a cover. A multi-threaded thread portion is formed on the outer peripheral surface of the rotating shaft, and a nut is screwed together. An output shaft is fixed to the nut, and when the rotary shaft is rotated by the electric motor, the output shaft is advanced and retracted together with the nut. The base of the output shaft is screwed and fixed to the nut.

  In the actuator described in Patent Document 2, the feed screw shaft is rotatably supported in the housing. This feed screw shaft is rotated and driven by a motor. A nut is threadably engaged with the feed screw shaft, and a hollow movable cylinder is connected to the nut. When the feed screw shaft is rotated and driven by the motor, the movable cylinder is advanced and retracted together with the nut. A female screw part is formed on the rear end side of the hollow part of the movable cylinder, and the female screw part is screwed into a male screw part formed on the nut so that the nut and the movable cylinder are connected. Yes.

  In the actuator described in Patent Document 3, a ball screw is rotatably installed in a hollow base, and a servo motor for rotating and driving the ball screw is installed on the rear side of the base. A ball nut is screwed to the ball screw, and a rod / nut coupling member is fixed to the ball nut, and a rod is screwed / coupled to the rod / nut coupling member. When the ball screw is rotated by the servo motor, the rod is advanced and retracted together with the nut.

JP 2000-152557 A Japanese Patent No. 4166499 Japanese Patent No. 4548923

The conventional configuration has the following problems.
In the case of the electric linear actuator described in Patent Document 1, the output shaft and the nut are screwed and fixed, and for this screwing and fixing, a female screw portion is formed on the base side of the output shaft and the above described There is a problem that the male thread portion must be formed on the nut, and the man-hours required for manufacturing the output shaft and the nut increase accordingly.
Similarly, in the case of the actuator described in Patent Document 2, an internal thread portion must be formed on the moving cylinder and an external thread portion must be formed on the nut. There was a problem of increasing.
Furthermore, in the case of the actuator described in Patent Document 3, it is necessary to prepare a rod / nut coupling member separately, which increases the number of parts and the man-hours required to manufacture the rod / nut coupling member. It was.

  The present invention has been made based on such points, and an object of the present invention is to provide an actuator capable of simplifying the configuration for connecting the ball screw nut and the rod, and thus facilitating manufacture. There is to do.

In order to achieve the above object, an actuator according to claim 1 of the present invention includes a housing, a ball screw shaft that is housed in the housing and rotated and driven, a ball screw nut that is screwed onto the ball screw shaft, and A rod that is crowned on the outer peripheral side of the ball screw nut, and a clamp mechanism that fixes the rod to the ball screw nut by tightening from the outside of the rod.
According to a second aspect of the present invention, in the actuator according to the first aspect, the rod is provided with an anti-rotation member for restricting the rotation of the ball screw nut and the rod by an engagement structure with the housing. The clamp mechanism is characterized by positioning and fixing the detent member to the rod.
According to a third aspect of the present invention, in the actuator according to the second aspect, a slit for providing a tightening allowance is formed on the proximal end side of the rod.
According to a fourth aspect of the present invention, in the actuator according to the third aspect, the anti-rotation member is provided with a convex portion that engages with the slit to determine the position of the anti-rotation member and restricts relative rotation with respect to the rod. It is characterized by being.
An actuator according to claim 5 is the actuator according to claim 2 or 3, wherein the detent member is provided separately from the clamp mechanism. is there.
According to a sixth aspect of the present invention, in the actuator according to the second or third aspect, the detent member is incorporated in the clamp mechanism.

As described above, according to the actuator according to claim 1 of the present invention, the housing, the ball screw shaft that is housed in the housing and is rotated and driven, the ball screw nut that is screwed to the ball screw shaft, A rod that is crowned on the outer peripheral side of the ball screw nut, and a clamp mechanism that fixes the rod to the ball screw nut by tightening from the outside of the rod. There is no need to form a screw part to fix the nut or other members, man-hours and the number of parts are reduced, the structure for connecting the ball screw nut and the rod is simplified, and manufacturing is facilitated. Can be achieved.
Further, according to the actuator according to claim 2, in the actuator according to claim 1, the rod is provided with an anti-rotation member for restricting rotation of the ball screw nut and the rod by an engagement structure with the housing, Since the clamp mechanism positions and fixes the detent member to the rod, the detent member can be easily positioned.
Further, according to the actuator according to claim 3, in the actuator according to claim 2, since a slit for providing a tightening allowance is formed on the proximal end side of the rod, when the rod is sandwiched by the clamp mechanism, The base end side is deformed, and the rod can be securely fixed to the ball screw nut.
According to an actuator according to claim 4, in the actuator according to claim 3, the detent member has a convex portion that engages with the slit to determine the position of the detent member and restricts relative rotation with respect to the rod. Since it is provided, positioning of the detent member and regulation of relative rotation with respect to the rod can be reliably and easily performed.
According to an actuator according to claim 5, in the actuator according to claim 2 or 3, the anti-rotation member is provided separately from the clamp mechanism. And the structure of the said clamp mechanism can be made simple.
Further, according to the actuator according to claim 6, in the actuator according to claim 2 or claim 3, since the detent member is incorporated in the clamp mechanism, the assembly is further facilitated. .

It is a figure which shows the 1st Embodiment of this invention and is a perspective view of an actuator. It is a figure which shows the 1st Embodiment of this invention, and is II-II sectional drawing of FIG. FIG. 3A is a cross-sectional view taken along the line IIIa-IIIa of FIG. 1 and FIG. 3B is a cross-sectional view taken along the line IIIb-IIIb of FIG. It is a figure which shows the 1st Embodiment of this invention and is an exploded perspective view of an actuator. 5A and 5B are views showing a first embodiment of the present invention, in which FIG. 5A is a perspective view of an assembled moving part unit and a ball screw shaft, and FIG. 5B is a moving part unit; It is the perspective view which looked at what assembled the ball screw axis from the back side. It is a figure which shows the 1st Embodiment of this invention, and is VI-VI sectional drawing of Fig.5 (a). It is a figure which shows the 1st Embodiment of this invention, and is an exploded perspective view of what assembled the moving part unit and the ball screw shaft. It is a figure which shows the 1st Embodiment of this invention and is a disassembled perspective view of a clamp mechanism. FIGS. 9A and 9B are views showing a second embodiment of the present invention, in which FIG. 9A is a perspective view of an assembly of a moving unit and a ball screw shaft as viewed from the front side, and FIG. It is the perspective view which looked at what assembled the ball screw axis from the back side. It is a figure which shows the 2nd Embodiment of this invention, and is XX sectional drawing of Fig.9 (a). It is a figure which shows the 2nd Embodiment of this invention, and is an exploded perspective view of what assembled the moving part unit and the ball screw shaft. FIG. 12A is an exploded perspective view of the clamp mechanism, and FIG. 12B is an exploded side view of the clamp mechanism, showing a second embodiment of the present invention.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
The actuator 1 according to the first embodiment includes a substantially cylindrical housing 3 as shown in FIGS. 1 to 3. On the inner peripheral surface of the housing 3, as shown in FIG. 2, guide grooves 5 and 5 extending in the length direction (perpendicular to the paper surface in FIG. 2) are formed at positions facing each other by 180 °. .
Further, as shown in FIGS. 3 (a) and 3 (b), a distal end cap mounting male screw portion 7 is formed on the outer peripheral surface of the housing on the distal end side (left side in FIG. 3 (a)). A bearing case mounting male screw portion 9 is formed on the outer peripheral surface of the rear end side (right side in FIG. 3A) of the housing.

A front end cap 11 is screwed and fixed to the front end side of the housing 3. As shown in FIGS. 3A and 3B, the tip cap 11 has a through hole 13 formed therein. The diameter of the rear end side (the right side in FIG. 3A) of the through hole 13 is increased, and a tip cap attaching female thread portion 15 is formed here. The tip cap attaching female screw portion 15 and the tip cap attaching male screw portion 7 of the housing 3 are screwed together, whereby the tip cap 11 is screwed and fixed to the housing 3.
Further, the distal end side (the left side in FIG. 3A) of the through hole 13 is reduced in diameter, and a bearing installation recess 17 is formed here. A cylindrical sliding bearing 18 is installed in the bearing installation recess 17.

  On the other hand, as shown in FIG. 3A, a bearing case 19 is installed on the rear end side of the housing 3 (on the right side in FIG. 3A). As shown in FIGS. 3A and 3B, the bearing case 19 is formed with a through hole 21. The front end side (the left side in FIG. 3A) of the through hole 21 is enlarged in diameter, and a bearing case mounting female thread portion 23 is formed here. The bearing case 19 is attached to the housing 3 by screwing the bearing case attaching male screw portion 9 of the housing 3 into the bearing case attaching female screw portion 23.

Further, the through hole 21 is formed with a bearing mounting recess 25 which is open on the tip side (left side in FIG. 3A). Bearings 27 are installed in the bearing mounting recess 25. The bearings 27, 27 are respectively an outer ring 29 that is in contact with the inner peripheral surface of the bearing mounting recess 25, an inner ring 31 that is installed inside the outer ring 29, and an inner ring 31 and the outer ring 29. The retainer 33 is disposed between the retainer 33 and a plurality of steel balls 35 that are held by the retainer 33 and roll between the inner ring 31 and the outer ring 29.
As shown in FIGS. 3 and 4, a bearing retainer 37 is installed on the distal end side (the left side in FIG. 3A) of the through hole 21. As shown in FIG. 4, a ball screw shaft penetrating slit 39 is formed in the bearing retainer 37. The bearing retainer 37 is inserted and fixed between the rear end surface of the housing 3 (the surface on the right side in FIG. 3) and the bearing case 19.
In addition, the rear end side (the right side in FIG. 3A) of the through hole 21 is also expanded to form a motor tip portion storing recess 41.

  A motor case 43 is installed on the rear end side (right side in FIG. 3A) of the bearing case 19. The motor case 43 is penetrated by a plurality of bolts (not shown), and these bolts are screwed into a female screw portion (not shown) formed at the rear end (the right end in FIG. 3A) of the bearing case 19. Thus, the bearing case 19 is fixed.

A motor 45 is installed in the motor case 43. The motor 45 has a motor housing 47, and a stator 49 is installed inside the motor housing 47. An output shaft 51 is rotatably installed inside the stator 49, and a rotor 53 is fixed to the output shaft 51.
An encoder 55 is installed on the rear end side (right side in FIG. 3A) of the motor 45, and the encoder 55 detects the rotation angle and the rotation speed of the output shaft 51.

A ball screw shaft 57 is installed in the housing 3 while being rotatably supported by the bearings 27 and 27. The ball screw shaft 57 includes a ball screw shaft main body 59 and a support portion 61 protruding from the rear end side (right side in FIG. 3A) of the ball screw shaft main body 59. A spiral groove 63 is formed on the outer peripheral surface of the ball screw shaft main body 59. The support portion 61 is press-fitted into the inner rings 31 and 31 of the bearings 27 and 27. Further, the support portion 61 protrudes from the bearings 27, 27 to the rear end side (right side in FIG. 3A) and is connected to the output shaft 51 of the motor 45 through a coupling mechanism 65. . The coupling mechanism 65 includes a ball screw shaft side hub 67 fixed to the support portion 61 of the ball screw shaft 57, a motor side hub 69 fixed to the output shaft 51 of the motor 45, and the ball screw shaft side. The intermediate disk 71 is engaged and inserted between the hub 67 and the motor-side hub 69.
The ball screw shaft 57 passes through the ball screw shaft penetrating slit 39 of the bearing retainer 37.

  Further, as shown in FIGS. 3A and 3B, a moving unit 73 is installed in the housing 3 so as to be movable in the front-rear direction (left-right direction in FIG. 3). As shown in FIGS. 5A and 5B, the moving unit 73 has a ball screw nut 75 first. The ball screw nut 75 is screwed onto the ball screw shaft 57. As shown in FIG. 6, the ball screw nut 75 has a substantially cylindrical ball screw nut body 77, and a spiral groove 79 is formed inside the ball screw nut body 77. In addition, a no-load circulation path 80 is formed in the ball screw nut body 77. A flange portion 81 is formed on the rear end side (right side in FIG. 6) of the ball screw nut body 77.

  An end cap 83 is installed on the front end side (left side in FIG. 6) of the ball screw nut body 77, and an end cap 85 is installed on the rear end side (right side in FIG. 6) of the ball screw nut body 77. ing. A return path 87 is formed in the end cap 83, and a return path 89 is formed in the end cap 85.

  The space between the spiral groove 79 of the ball screw nut 75 and the spiral groove 63 of the ball screw shaft 57, the return path 87 of the end cap 83, the no-load circulation path 80, and the return of the end cap 85. A plurality of steel balls 90 roll and circulate in the path 89. With this configuration, the ball screw nut 75 is movably screwed to the ball screw shaft 57.

For example, as shown in FIG. 6, a rod 91 is installed on the tip side (left side in FIG. 6) of the ball screw nut 75. The rod 91 is a substantially cylindrical member, and as shown in FIGS. 6 and 7, slits 93 and 93 opened to the rear end side are formed in the rear end portion. The ball screw nut 75 is inserted into the rear end side of the rod 91 until the flange portion 81 comes into contact with the rear end surface of the rod 91 (the right side surface in FIG. 6).
As shown in FIG. 3A, a tip member 94 is fixed to the tip of the rod 91 (the left end in FIG. 3A).
Further, the distal end side (left end side in FIG. 3A) of the rod 91 penetrates the through hole 13 of the distal end cap 11 and protrudes forward (left side in FIG. 3A). The rod 91 is slidably supported by a sliding bearing 18 installed on the tip cap 11.

  The rod 91 is provided with a detent member 95. As shown in FIG. 7, the anti-rotation member 95 is arranged on the outer peripheral surface of the rod 91 and the anti-rotation portions 97, 97 arranged on both sides in the width direction (the direction from the upper left to the lower right in FIG. 7). It comprises arcuate connecting portions 99, 99 that connect the anti-rotating portions 97, 97. As shown in FIGS. 6 and 7, rod engaging projections 101, 101 are formed on the inner side of the detent member 95, and these rod engaging projections 101, 101 are slits of the rod 91. 93 and 93 are inserted and engaged. The anti-rotation member 95 is inserted until the rod engaging convex portions 101 and 101 come into contact with the front end surfaces of the slits 93 and 93 (the left end surface in FIG. 6).

  The anti-rotation portions 97 and 97 are inserted into the guide grooves 5 and 5 of the housing 3 as shown in FIG. Further, as shown in FIG. 7, the anti-rotation portion 97 has a tip side (lower left side in FIG. 7) divided into two in the vertical direction in FIG. Portions 103 and 103 are formed. When the anti-rotation portion 97 is inserted into the guide groove 5, the contact convex portions 103 and 103 are brought into contact with the inner side surfaces (surfaces on both sides in the direction perpendicular to the paper surface in FIG. 3) of the guide groove 5. The tip of the rotation preventing portion 97 is elastically deformed. Thereby, the vibration when the rod 91 moves in the housing 3 is absorbed.

For example, as shown in FIG. 5B, a clamp mechanism 105 is provided on the rear end side of the rod 91 (lower right side in FIG. 5B). As shown in FIG. 8, the clamp mechanism 105 includes a substantially C-shaped clamp member 107, bolts 109 and 109 and nuts 111 and 111 that fasten both ends of the clamp member 107.
For example, as shown in FIG. 6, the rear end portion of the rod 91 and the ball screw nut 75 are arranged inside the clamp member 107, and the bolts 109 and 109 and the nuts 111 and 111 are tightened. The rod 91 and the ball screw nut 75 are fastened by the clamp member 107 due to the deformation of the clamp member 107.
Further, as described above, the anti-rotation member 95 is inserted until the rod engaging convex portions 101, 101 are in contact with the end surfaces (left end surface in FIG. 6) of the slits 93, 93 of the rod 91, By positioning the clamp member 107 in contact with the rear end side of the anti-rotation member 95, the anti-rotation member 95 is positioned and prevented from falling off.

Next, the operation of the first embodiment will be described.
First, the operation of the actuator 1 will be described.
When the ball screw shaft 57 is rotated forward or reverse by the motor 45, a force acts so as to be rotated also on the ball screw nut 75 and the rod 91. However, since the rotation of the ball screw nut 75 and the rod 91 around the ball screw shaft 57 is restricted by the anti-rotation member 95 and the guide groove 5 of the housing 3, the ball screw nut 75 and the rod 91 move forward along the guide groove 5. Or retreated.

Next, assembly of the moving unit 73 of the actuator 1 will be described.
First, the rod engaging convex portions 101 and 101 of the rotation preventing member 95 are inserted and engaged with the slit 93 of the rod 91, and the rod engaging convex portions 101 and 101 are inserted into the slit 93. , 93 are moved until they come into contact with the front end surface (left end surface in FIG. 6).
Next, the clamp mechanism 105 is attached to the rod 91 from the rear end side (right side in FIG. 6).
Next, a ball screw nut 75 is inserted into the rear end side (right side in FIG. 6) of the rod 91, and the flange portion 81 of the ball screw nut 75 is connected to the rear end surface of the rod 91 (right end surface in FIG. 6). Make contact.
A ball screw shaft 57 is screwed into the ball screw nut 75 in advance.
Next, the clamp member 107 is tightened by the bolts 109 and 109 and the nuts 111 and 111 in a state where the clamp mechanism 105 is urged toward the anti-rotation member 95. As a result, the rear end of the rod 91 is pressed radially inward within the range of the slit 93, and the rod 91 and the ball screw nut 75 are clamped and fixed by the clamp mechanism 105. Further, the anti-rotation member 95 is interposed between the front end surface of the slit 93 (the left end surface in FIG. 6) and the clamp mechanism 105, whereby the anti-rotation member 95 is positioned and fixed.

Next, the effect of the first embodiment will be described.
First, the structure for connecting the ball screw nut 75 and the rod 91 can be simplified, and the manufacturing can be facilitated. That is, since the rod 91 and the ball screw nut 75 are sandwiched and fixed by the clamp mechanism 105, for example, it is necessary to form a threaded portion for fixing the ball screw nut 75 to the rod 91, and the like. It is not necessary to prepare these members, man-hours and the number of parts are reduced, and the actuator 1 can be easily manufactured.
In addition, since the slit 91 is formed in the rod 91, when the clamp mechanism 105 sandwiches the rod 91, the slit 91 side of the rod 91 is deformed inward, and the ball screw nut 75 is securely sandwiched and fixed. Can do.
Further, since the rod engaging projections 101 and 101 are provided on the anti-rotation member 95 and the rod engagement projections 101 and 101 are inserted into and engaged with the slits 93 and 93 of the rod 91. The rotation preventing member 95 can be securely attached.
Further, the rod engaging projections 101 and 101 of the anti-rotation member 95 are inserted until they come into contact with the front end surfaces (left surfaces in FIG. 6) of the slits 93 and 93, and the anti-rotation member 95 is Since it is inserted between the clamp mechanism 105 and the rod 91, the detent member 95 can be positioned reliably and easily.

Next, a second embodiment of the present invention will be described with reference to FIGS.
The actuator according to the second embodiment has substantially the same configuration as the actuator 1 according to the first embodiment, except that a moving unit 121 as shown in FIGS. 9 and 10 is used. Is different.

  The moving unit 121 has substantially the same configuration as the moving unit 73 of the actuator 1 according to the first embodiment, but differs in that a clamp mechanism 123 is used.

As shown in FIGS. 11 and 12, the clamp mechanism 123 includes a first clamp member 125 and a second clamp member 127.
For example, as shown in FIGS. 12A and 12B, the first clamp member 125 has a notch 129 formed on the upper side of the substantially cylindrical member on the left end side in FIG. 12B. It has a different shape. A locking member engaging recess 131 is formed on the outer peripheral surface of the first clamp member 125 on both sides in the vertical direction on the right end side in FIG. Further, as shown in FIG. 12A, the notch 129 and the first clamp member 125 in FIG. 12 are arranged on the front end side of the first clamp member 125 (the left lower end side in FIG. 12A). (A) Female screw parts 133 and 133 opened on the lower side in the middle are formed. Further, in the portion of the first clamp member 125 where the female screw portions 133 and 133 are opened (the lower side in FIG. 12A), the bolt storage recesses 135 and 135 (one bolt storage recess 135 is (Not shown) is formed.

  The second clamp member 127 has a shape obtained by dividing a cylindrical member corresponding to the notch 129 of the first clamp member 125 in half. The second clamp member 127 is installed in the notch 129 of the first clamp member 125. The second clamp member 127 has through holes 137 and 137 (one through hole 137 is not shown). In addition, in the upper part of the second clamp member 127 in FIG. 12A and where the through-holes 137 and 137 are opened, bolt storage recesses 139 and 139 (one bolt storage recess 139 is provided). (Not shown) is formed. In addition, the first clamp member 125 and the second clamp member 127 pass the bolts 141 and 141 through the through holes 137 and 137 of the second clamp member 127, and the female screw portions 133 and 133 of the first clamp member 125. It is fastened and fixed by being screwed onto.

  For example, as shown in FIGS. 9A and 10, a rod 91 is inserted between the first clamp member 125 and the second clamp member 127, and the rear end side of the rod 91 is inserted. Since the ball screw nut 75 is inserted (on the right end side in FIG. 10), the rod 91 and the ball screw nut 75 are secured by fastening and fixing the first clamp member 125 and the second clamp member 127. Are connected and fixed.

Further, by engaging the anti-rotation members 143 and 143 with the anti-rotation member engaging recesses 131 and 131 of the first clamp member 125, the anti-rotation members 143 and 143 are incorporated into the clamp mechanism 123. The anti-rotation members 143 and 143 are engaged with guide grooves 5 and 5 (shown in FIGS. 2 and 3) formed in the housing 3, whereby the ball screw nut 75 and the rod 91 are engaged. Is guided on both sides in the front-rear direction (the direction from the lower left to the upper right in FIG. 9A), and the rotation about the ball screw shaft 57 is restricted.
The same parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

Next, the operation of the second embodiment will be described.
First, the operation of the actuator according to the second embodiment is the same as the operation of the actuator 1 according to the first embodiment.

Next, assembly of the moving unit 121 will be described.
First, the ball screw nut 75 is inserted into the rear end side (right side in FIG. 10) of the rod 91, and the flange portion 81 of the ball screw nut 75 is brought into contact with the rear end surface (right end surface in FIG. 10) of the rod 91. Let
A ball screw shaft 57 is screwed into the ball screw nut 75 in advance.
Next, the rear end side (right side in FIG. 10) of the rod 91 is sandwiched between the first clamp member 125 and the second clamp member 127, and the bolts 141 and 141 are passed through the through holes 137 and 137 of the second clamp member 127. The first clamp member 125 is screwed into the female screw parts 133 and 133.
Next, the bolts 141 and 141 are tightened, and the rear end of the rod 91 is pressed radially inward within the slit 93 by the first clamp member 125 and the second clamp member 127. As a result, the rod 91 and the ball screw nut 75 are clamped and fixed by the first clamp member 125 and the second clamp member 127.

In the case of the second embodiment, the same effect as that of the first embodiment can be obtained.
However, since the anti-rotation member 95 inserted in the slits 93 and 93 of the rod 91 is not installed, the effect regarding this anti-rotation member 95 is not show | played.
In the case of the second embodiment, instead of the anti-rotation member 95, the anti-rotation members 143 and 143 are engaged with the anti-rotation member engaging recesses 131 and 131 of the first clamp member 125. The configuration can be simplified.

The present invention is not limited to the first embodiment and the second embodiment.
It is also conceivable that a convex portion is formed on the inner peripheral surface of the housing, a concave portion is formed on the rotation preventing member, and the concave portion and the convex portion are engaged.
In addition, the illustrated configuration is an example, and various cases are conceivable.

  The present invention relates to a rod-type actuator, and relates to a device devised so as to simplify the configuration for connecting a ball screw nut and a rod, and to facilitate manufacturing, and is used, for example, in an industrial robot. Suitable for actuator.

DESCRIPTION OF SYMBOLS 1 Actuator 3 Housing 57 Ball screw shaft 75 Ball screw nut 91 Rod 93 Slit 95 Anti-rotation member 101 Rod engagement convex part 105 Clamp mechanism 123 Clamp mechanism 143 Anti-rotation member

Claims (6)

A housing;
A ball screw shaft that is housed in the housing and rotated and driven;
A ball screw nut screwed onto the ball screw shaft;
A rod to be crowned on the outer peripheral side of the ball screw nut;
A clamp mechanism for fixing the rod to the ball screw nut by tightening from the outside of the rod;
An actuator characterized by comprising: The actuator according to claim 1, wherein
The rod is provided with an anti-rotation member for restricting the rotation of the ball screw nut and the rod due to the engagement structure with the housing,
The actuator according to claim 1, wherein the clamp mechanism positions and fixes the detent member to the rod. The actuator according to claim 2, wherein
An actuator characterized in that a slit for providing a tightening allowance is formed on the proximal end side of the rod. The actuator according to claim 3, wherein
The actuator according to claim 1, wherein the anti-rotation member is provided with a convex portion that engages with the slit to determine the position of the anti-rotation member and restricts relative rotation with respect to the rod. The actuator according to any one of claims 2 and 3,
The actuator according to claim 1, wherein the anti-rotation member is provided separately from the clamp mechanism. The actuator according to any one of claims 2 and 3,
The actuator according to claim 1, wherein the anti-rotation member is incorporated in the clamp mechanism.

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